Vania



(NOMOM') G. B. PRALEY an A.. B. PAULsovseets`sheetl' BLEGTRKIO HEATER.

Patented June 29, 189'?` (No Model.) 2 Sheets-8heet 2.

G. B. FRALEY 8v A. B..PAULSON. ELECTRIC HEATER Patented June 29,1897.

UNITED STATES PATENT OEEicE.

' GEORGE B. FRALEY AND AMOS B. PAULSON, OF PHILADELPHIA, PENNSYL- VANIA, ASSIGNORS TO THE GLOBE ELECTRIC HEATING COMPANY, OF

SAME PLACE.

ELECTRIC HEATER.

SPECIFICATION forming part of Letters Patent No. 585,311, dated June 29, 189'?.

Application filed September 2l, 1896. Serial No. 606,536. (No model.)

To @ZZ whom, t may concern:

Be it known that we, GEORGE B. FRALEY and AMOS B. PAULSON, of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Electric Heaters; and We do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the numerals of reference marked thereon,which form part of this speciiication.

This invention relates to electric heaters, and has for its objects to simplify their construction, increase their effectiveness, and at the same time adapt them for use with either a direct or alternating current, as may be desired.

Iith these objects in view the invention consists in the improved construction, arrangement, and combination of parts hereinafter fully described, and specifically pointed out in the claims.

In the accompanying drawings, Figure l is a longitudinal vertical sectional view of a core for direct current and attachments, the position of the insulating and protecting cover being shown in dotted lines. Fig. 2 is a similar vie w of the same parts with two reflectors in position inside the tubular core. Fig. 3 is a similar view of the same parts in a modified form,the reflectors being mounted beyond the ends of the tubular core. Figs. 4 and 5 are views in opposite side elevations of a modiiied form of core for use with an alternating current. Fig. 6 is a view in side elevation of the lower portion of a core and attachments and the base on which it is to be mounted and through which the connections with core and coils are made. Fig. 7 is a bottom plan view of the base. Fig. 8 is a central vertical sectional view ot' the same. Fig. 0 is a view in elevation of a heater composed of a battery of coils, part of the jacket being broken away g and Fig. 10 is a top plan view of the saine.

Like numerals of reference mark the same parts wherever they occur in the various iigures of the drawings.

Referring to the drawings by numerals, l is a tubular core, of copper or other suitable material. There are illustrated in the drawings three forms of cores, one being intended for use with a direct current and illustrated in detail in Figs. 1, 2, and 3 and two for use with an alternating current and illustrated in Figs. 4 and 5.

The cores are covered with a sheet of mica, as at 2, and a sheet 3 of asbestos or other nonconductor, around which is coiled any desired number of wires 1t. In all the figures which illustrate the wires but one wire is shown, eX- cept in Fig. 1, in which two are shown. The black line next to the core is intended to illustrate the mica, and where two or more coiled wires are used, as in Fig. 1, the separate coils may be separated by sheets of asbestos, as shown at 5 in Fig. 1.

6 is a metal cap made at 6 of a sufcient diameter t-o embrace the lower end of the core, for which purpose the core extends slightly below its coverings. The cap G is of reduced diameter below the part G and formed with a screw-thread, as at 7, the lower end being closed by a perforated head S, of porcelain or other insulating material. Through the perforation of the head 8 is passed a screw 0, which is provided with a large head (or a washer under the head) 10.

The screw-thread 7 of cap 6 engages in a similarly-threaded metal thimble 11 in a base 12, formed of porcelain or other insulating material, (see Figs. 7 and 8,) which engages a metal plate 13, extending out through an opening 14 in said base 12 and provided at its outer end with a suitable bindingsscrew 15. The head 10 of screw 9 comes in contact with another plate 17, which extends through an opening 1S in the opposite side of base 12 and having at its outer end a suitable bindingscrew 19. The inner end of the screw 9 inside of the porcelain head 8 is formed as a binding-screwto engage the lower end of the coiled wire l, in this instance, Figs. l and Q, I forretardingthe ilowof said air. lheheater being provided with a washer and nut 2l, between which the wire is clamped.

By means of the construction described a complete circuit is formed, the wire from the electric supply being engaged by bindingscrew l), the current passing through plate I7, screw t), into and through the conductors l, which are continuous and extend in Fig. l iirst upwardly and then downwardly around the exterior insulation 5, the contact being made with the cap (i at the point 22, thence by the binding-screw I5.

In Fig. 2 but one coil of wire is shown. Here the upper end of the wire is connected at to the upper end of the core I.

The core, wires, 5cc., are covered with any suitable coating of a goed heat-conducting but insulating substance, as shown by dotted lines at 23, Fig. l. The current passing through the wires and core, as described, gencrates a high degree of heat therein, and air at normal temperature entering the ports 'P in the lower portion of the core becomes highly heated in its passage therethrough prior te its exit at the top of said core.

A heater maybe composed of a single core audits appurtenances, as described, or anumber of cores may be connected, as shown in Figs. Q and IO, and used as a battery, being inelosed bya jacket 25 and mounted on a suitable base 2G.

rlhe cere described is intended ier use with a direct current, and it may be slotted from end to end, as at 2st, Fig. l, to provide for expansion and contraction from heat and cold.

In the construction seen in Figs. -l and 5 the cores seen therein are in practice surrounded by a primary coil, an induced current being created in said cores in the inanner already described. The cores seen in Figs. #l and 5 are slotted from the top nearly to the bottom at SO and on the opposite side from the bottom nearly to the top at 3l, whereby a free expansion and contraction is permitted, and since the core is not slotted continuously from end to end a secondary current is crea-ted, as already described, in the direction of the arrows.

32 designates suitable reflectors. (Best seen in Figs. 2 and 3.) In Fig. 3 these reflectors are secured to the core 1 so that they are removed a suitable distance from each extremity o't said core. This arrangement largely increases the heating capacity; but a still better result is attained by the arrangement shown in Fig. 3, in which the refiectors are placed inside the cere near the opposite ends thereof, their concave faces opposite to each other.

It will be seen from the foregoing that the underlying feature of our invention is a core or tube with a resistance wound thereon, said tube being open at both ends, so that air may ilow therethrough, and provided with means gives up units of heat by radiation and convection, it being apparent that if the tube had an unobstructed passage therethrough the large quantity of air [lowing therethrough, acting as a heat vehicle, will carry away so many units of heatas to reduce the temperature ot' the resistance to such an extent as to impair its eiliciency. rl'he above conditions are avoided by retarding the Ilow of air through the core, so as to prevent the maximum number of heat-units from being earried away by convection, this retardation being effected by the employment of one or more reflectors suitably supported upon said core. The detention of the air within the tube prevents the fall of temperature in the resistance itself and thereby reduces the current; but the temperature of the resistance is not liable to rise to an undesirable degree, since the hotter the air becomes the greater will be its buoyancy and velocity and the greater the number of heat-units removed from the interior of the heater. The reilectors employed, being preferably of metal,be come highly heated and serve as battle-plates for the purpose of retaining the heated air within the core as long as possible.

It will of course be evident that any suitable material may be employed in the construction of the core l and that, if desired, the reflectors 32 maybe concaved and polished, as well as the interior of the core, but we do not desire to be restricted thereto in every instance. It will further be apparent that changes may be made by those skilled in the art which will come within the scope of our invention, and we do not therefore desire to be limited in every instance to the exact construction we have herein shown and described.

That we claim isl. In an electric heater, the combination of a slotted core, and a resistance-coil, wound around said core.

2. In an electric heater, the combination of a metallic core, slotted for a portion ot its length and au insulated resistance-coil wound around said core.

3. In an electric heater, a core, having a plurality of slots therein, beginning alternately at opposite ends, the length of said slots being less than the length ol' said core, the latter forming a secondary circuit and an insulated primarycoil surrounding said core.

3t. In an electric heater, a core having a plurality of slots therein, beginning alternately at opposite ends, the length of said slots being less than the length oi' said core, the latter forming a secondary circuit, and a primary resistance-coil surrounding said core.

5. In an electric heater, the con'ibinatien of a core, a resistance-coil, wound around said core, and a reflector suitably supported, adjacent an end of said core.

IIO

Gc. In an electric heater, the combination ot a core7 a resistance-coil Wound around said core, and a reflector located adjacent each end of said core. 4

7. In an electric heater7 the combination of a core, a resistance-coll wound around said core, and a reflector located Within said core intermediate the ends thereof.

8. In an electric heater, the combination of a core, a resistance-coil Wound around Said core, and concave reflector located near each end of said core, the concave surfaces of the reflectors facing; each other.

In testimony that We claim the foregoing as our own We alTrx our signatures in presence I5 of two Witnesses.

GEORGE B. FRALEY. AMOS B. PAULSON.

lVtnesses:

JOHN F. TURNER,

ALBERT E. Porre. 

